<!DOCTYPE html>
<html lang="en">
	<head>
		<meta charset="utf-8" />
		<base href="../../../" />
		<script src="page.js"></script>
		<link type="text/css" rel="stylesheet" href="page.css" />
	</head>
	<body>
		[page:Mesh] &rarr;

		<h1>[name]</h1>

		<p class="desc">
			A special version of [page:Mesh] with multi draw batch rendering support. Use
			[name] if you have to render a large number of objects with the same
			material but with different world transformations. The usage of [name] will
			help you to reduce the number of draw calls and thus improve the overall
			rendering performance in your application.

			<br/>
			<br/>

			If the [link:https://developer.mozilla.org/en-US/docs/Web/API/WEBGL_multi_draw WEBGL_multi_draw extension] is
			not supported then a less performant fallback is used.
		</p>

		<h2>Code Example</h2>

		<code>
		const box = new THREE.BoxGeometry( 1, 1, 1 );
		const sphere = new THREE.SphereGeometry( 1, 12, 12 );
		const material = new THREE.MeshBasicMaterial( { color: 0x00ff00 } );

		// initialize and add geometries into the batched mesh
		const batchedMesh = new BatchedMesh( 10, 5000, 10000, material );
		const boxGeometryId = batchedMesh.addGeometry( box );
		const sphereGeometryId = batchedMesh.addGeometry( sphere );

		// create instances of those geometries
		const boxInstancedId1 = batchedMesh.addInstance( boxGeometryId );
		const boxInstancedId2 = batchedMesh.addInstance( boxGeometryId );

		const sphereInstancedId1 = batchedMesh.addInstance( sphereGeometryId );
		const sphereInstancedId2 = batchedMesh.addInstance( sphereGeometryId );

		// position the geometries
		batchedMesh.setMatrixAt( boxInstancedId1, boxMatrix1 );
		batchedMesh.setMatrixAt( boxInstancedId2, boxMatrix2 );

		batchedMesh.setMatrixAt( sphereInstancedId1, sphereMatrix1 );
		batchedMesh.setMatrixAt( sphereInstancedId2, sphereMatrix2 );

		scene.add( batchedMesh );
		</code>

		<h2>Examples</h2>
		<p>
			[example:webgl_mesh_batch WebGL / mesh / batch]<br />
		</p>

		<h2>Constructor</h2>
		<h3>
			[name](
				[param:Integer maxInstanceCount], [param:Integer maxVertexCount],
				[param:Integer maxIndexCount], [param:Material material],
			)
		</h3>
		<p>
			[page:Integer maxInstanceCount] - the max number of individual instances planned to be added and rendered.<br />
			[page:Integer maxVertexCount] - the max number of vertices to be used by all unique geometries.<br />
			[page:Integer maxIndexCount] - the max number of indices to be used by all unique geometries.<br />
			[page:Material material] - an instance of [page:Material]. Default is a new [page:MeshBasicMaterial].<br />
		</p>

		<h2>Properties</h2>
		<p>See the base [page:Mesh] class for common properties.</p>

		<h3>[property:Box3 boundingBox]</h3>
		<p>
			This bounding box encloses all instances of the [name]. Can be calculated
			with [page:.computeBoundingBox](). Default is `null`.
		</p>

		<h3>[property:Sphere boundingSphere]</h3>
		<p>
			This bounding sphere encloses all instances of the [name]. Can be
			calculated with [page:.computeBoundingSphere](). Default is `null`.
		</p>

		<h3>[property:Boolean perObjectFrustumCulled]</h3>
		<p>
			If true then the individual objects within the [name] are frustum culled. Default is `true`.
		</p>

		<h3>[property:Boolean sortObjects]</h3>
		<p>
			If true then the individual objects within the [name] are sorted to improve overdraw-related artifacts.
			If the material is marked as "transparent" objects are rendered back to front and if not then they are
			rendered front to back. Default is `true`.
		</p>

		<h3>[property:Integer maxInstanceCount]</h3>
		<p>
			The maximum number of individual instances that can be stored in the [name]. Read only.
		</p>

		<h3>[property:Boolean isBatchedMesh]</h3>
		<p>Read-only flag to check if a given object is of type [name].</p>

		<h2>Methods</h2>
		<p>See the base [page:Mesh] class for common methods.</p>

		<h3>[method:undefined computeBoundingBox]()</h3>
		<p>
			Computes the bounding box, updating [page:.boundingBox] attribute.<br />
			Bounding boxes aren't computed by default. They need to be explicitly
			computed, otherwise they are `null`.
		</p>

		<h3>[method:undefined computeBoundingSphere]()</h3>
		<p>
			Computes the bounding sphere, updating [page:.boundingSphere]
			attribute.<br />
			Bounding spheres aren't computed by default. They need to be explicitly
			computed, otherwise they are `null`.
		</p>

		<h3>[method:undefined dispose]()</h3>
		<p>
			Frees the GPU-related resources allocated by this instance. Call this
			method whenever this instance is no longer used in your app.
		</p>

		<h3>[method:this setCustomSort]( [param:Function sortFunction] )</h3>
		<p>
			Takes a sort a function that is run before render. The function takes a list of instances to sort and a camera. The objects
			in the list include a "z" field to perform a depth-ordered sort with.
		</p>

		<h3>
			[method:undefined getColorAt]( [param:Integer instanceId], [param:Color target] )
		</h3>
		<p>
			[page:Integer instanceId]: The id of an instance to get the color of.
		</p>
		<p>
			[page:Color target]: The target object to copy the color in to.
		</p>
		<p>Get the color of the defined geometry.</p>

		<h3>
			[method:Matrix4 getMatrixAt]( [param:Integer instanceId], [param:Matrix4 target] )
		</h3>
		<p>
			[page:Integer instanceId]: The id of an instance to get the matrix of.
		</p>
		<p>
			[page:Matrix4 target]: This 4x4 matrix will be set to the local
			transformation matrix of the defined instance.
		</p>
		<p>Get the local transformation matrix of the defined instance.</p>

		<h3>
			[method:Boolean getVisibleAt]( [param:Integer instanceId] )
		</h3>
		<p>
			[page:Integer instanceId]: The id of an instance to get the visibility state of.
		</p>
		<p>Get whether the given instance is marked as "visible" or not.</p>

		<h3>
			[method:undefined setColorAt]( [param:Integer instanceId], [param:Color color] )
		</h3>
		<p>
			[page:Integer instanceId]: The id of the instance to set the color of.
		</p>
		<p>[page:Color color]: The color to set the instance to.</p>
		<p>
			Sets the given color to the defined geometry instance.
		</p>

		<h3>
			[method:this setMatrixAt]( [param:Integer instanceId], [param:Matrix4 matrix] )
		</h3>
		<p>
			[page:Integer instanceId]: The id of an instance to set the matrix of.
		</p>
		<p>
			[page:Matrix4 matrix]: A 4x4 matrix representing the local transformation
			of a single instance.
		</p>
		<p>
			Sets the given local transformation matrix to the defined instance.
		</p>

		<h3>
			[method:this setVisibleAt]( [param:Integer instanceId], [param:Boolean visible] )
		</h3>
		<p>
			[page:Integer instanceId]: The id of the instance to set the visibility of.
		</p>
		<p>
			[page:Boolean visible]: A boolean value indicating the visibility state.
		</p>
		<p>
			Sets the visibility of the instance at the given index.
		</p>

		<h3>
			[method:Integer addGeometry]( [param:BufferGeometry geometry], [param:Integer reservedVertexRange], [param:Integer reservedIndexRange] )
		</h3>
		<p>
			[page:BufferGeometry geometry]: The geometry to add into the [name].
		</p>
		<p>
			[page:Integer reservedVertexRange]: Optional parameter specifying the amount of vertex buffer space to reserve for the added geometry. This
			is necessary if it is planned to set a new geometry at this index at a later time that is larger than the original geometry. Defaults to
			the length of the given geometry vertex buffer.
		</p>
		<p>
			[page:Integer reservedIndexRange]: Optional parameter specifying the amount of index buffer space to reserve for the added geometry. This
			is necessary if it is planned to set a new geometry at this index at a later time that is larger than the original geometry. Defaults to
			the length of the given geometry index buffer.
		</p>
		<p>
			Adds the given geometry to the [name] and returns the associated geometry id referring to it to be used in other functions.
		</p>

		<h3>
			[method:Integer addInstance]( [param:Integer geometryId] )
		</h3>
		<p>
			[page:Integer geometryId]: The id of a previously added geometry via "addGeometry" to add into the [name] to render.
		</p>
		<p>
			Adds a new instance to the [name] using the geometry of the given geometryId and returns a new id referring to the new instance to be used
			by other functions.
		</p>

		<h3>
			[method:Integer setGeometryAt]( [param:Integer geometryId], [param:BufferGeometry geometry] )
		</h3>
		<p>
			[page:Integer geometryId]: Which geometry id to replace with this geometry.
		</p>
		<p>
			[page:BufferGeometry geometry]: The geometry to substitute at the given geometry id.
		</p>
		<p>
			Replaces the geometry at `geometryId` with the provided geometry. Throws an error if there is not enough space reserved for geometry.
			Calling this will change all instances that are rendering that geometry.
		</p>

		<!--
		<h3>
			[method:Integer getInstanceCountAt]( [param:Integer index] )
		</h3>
		<p>
			[page:Integer index]: The index of an instance. Values have to be in the
			range [0, count].
		</p>
		<p>
			Gets the instance count of the geometry at `index`. Returns `null` if instance counts are not configured.
		</p>

		<h3>
			[method:Integer setInstanceCountAt]( [param:Integer index], [param:Integer instanceCount ] )
		</h3>
		<p>
			[page:Integer index]: Which geometry index to configure an instance count for.
		</p>
		<p>
			[page:Integer instanceCount]: The number of instances to render of the given geometry index.
		</p>
		<p>
			Sets an instance count of the geometry at `index`.
		</p>
		-->

		<h2>Source</h2>

		<p>
			[link:https://github.com/mrdoob/three.js/blob/master/src/[path].js src/[path].js]
		</p>
	</body>
</html>
